|This article is about a/an parent in Chikyuu Sentai Fiveman.|
Doctor Hoshikawa is the father of the five Hoshikawa siblings who would later become the Fivemen. Twenty years ago before the events of the series, Doctor Hoshikawa was researching how to transform the planet Sedon into a green, lush world, testing it by attempting to grow flowers. On the day the first flower bloomed, Zone launched an assault on the planet, he and his wife were separated from their five children. Arthur G6 took the five children back to Earth and raised them.